// Copyright (c) 1997-2000  Max-Planck-Institute Saarbruecken (Germany).
// All rights reserved.
//
// This file is part of CGAL (www.cgal.org); you may redistribute it under
// the terms of the Q Public License version 1.0.
// See the file LICENSE.QPL distributed with CGAL.
//
// Licensees holding a valid commercial license may use this file in
// accordance with the commercial license agreement provided with the software.
//
// This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
// WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
//
// $URL$
// $Id$
// 
//
// Author(s)     : Michael Seel <seel@mpi-sb.mpg.de>

#ifndef CGAL_NEF_POLYNOMIAL_H
#define CGAL_NEF_POLYNOMIAL_H

#include <CGAL/Nef_2/Polynomial.h>
//#include <CGAL/basic.h>
//#include <CGAL/kernel_assertions.h>
//#include <CGAL/Handle_for.h>
//#include <CGAL/number_type_basic.h>
//#include <CGAL/number_utils.h>
//#include <CGAL/Number_type_traits.h>
//#include <CGAL/IO/io.h>
#include <cstddef>
#undef CGAL_NEF_DEBUG
#define CGAL_NEF_DEBUG 3
#include <CGAL/Nef_2/debug.h>
#include <vector>

#include <CGAL/Kernel/mpl.h>

#include <boost/operators.hpp>

CGAL_BEGIN_NAMESPACE

#define CGAL_int(T)    typename First_if_different<int,    T>::Type
#define CGAL_double(T) typename First_if_different<double, T>::Type

template <class NT> 
class Nef_polynomial
  : boost::ordered_field_operators1< Nef_polynomial<NT>
  , boost::ordered_field_operators2< Nef_polynomial<NT>, int
  > >
  , public Nef::Polynomial<NT>
{
  typedef typename CGAL::Nef::Polynomial<NT>  Base;
  typedef typename Base::size_type       size_type;

 protected:
  Nef_polynomial(size_type s) : Base(s) {}

 public:
  Nef_polynomial() : Base() {}
  Nef_polynomial(const NT& a0) : Base(a0) {}
  Nef_polynomial(const NT& a0, const NT& a1) : Base(a0,a1) {}
  Nef_polynomial(const NT& a0, const NT& a1, const NT& a2) : Base(a0,a1,a2) {}

  template <class Fwd_iterator>
  Nef_polynomial(std::pair<Fwd_iterator, Fwd_iterator> poly) : Base(poly) {}

  Nef_polynomial(CGAL_double(NT) n) : Base(n) {}
  Nef_polynomial(CGAL_double(NT) n1, CGAL_double(NT) n2) : Base(n1, n2) {}
  Nef_polynomial(CGAL_int(NT) n) : Base(NT(n)) {}
  Nef_polynomial(CGAL_int(NT) n1, CGAL_int(NT) n2) : Base(n1,n2) {}

  Nef_polynomial(const Base& p) : Base(p) {}

  Base & polynomial() { return static_cast<Base&>(*this); }
  const Base & polynomial() const  { return static_cast<const Base&>(*this); }

    static NT& infi_maximal_value() {
      static NT R_ = 1;
      return R_;
    }
};

template <class NT> 
inline
Nef_polynomial<NT> operator+(const Nef_polynomial<NT> &a)
{
  return a;
}

template <class NT> 
inline
Nef_polynomial<NT> operator-(const Nef_polynomial<NT> &a)
{
  return - a.polynomial();
}

template <class NT> 
inline
bool operator<(const Nef_polynomial<NT> &a, const Nef_polynomial<NT> &b)
{
  return a.polynomial() < b.polynomial();
}

template <class NT> 
inline
bool operator==(const Nef_polynomial<NT> &a, const Nef_polynomial<NT> &b)
{
  return a.polynomial() == b.polynomial();
}

template <class NT> 
inline
bool operator==(const Nef_polynomial<NT> &a, int b)
{
  return a.polynomial() == b;
}

template <class NT> 
inline
bool operator<(const Nef_polynomial<NT> &a, int b)
{
  return a.polynomial() < b;
}

template <class NT> 
inline
bool operator>(const Nef_polynomial<NT> &a, int b)
{
  return a.polynomial() > b;
}


#undef CGAL_double
#undef CGAL_int


// TODO: integral_division to get it an UniqueFactorizationDomain
// TODO: div / mod  for EuclideanRing
template <class NT> class Algebraic_structure_traits< Nef_polynomial<NT> >
    : public Algebraic_structure_traits_base
             < Nef_polynomial<NT>, CGAL::Integral_domain_without_division_tag> 
{
    typedef Algebraic_structure_traits<NT> AST_NT;
public:
    typedef Nef_polynomial<NT> Type;
    typedef typename AST_NT::Is_exact            Is_exact;
    typedef Tag_false                            Is_numerical_sensitive;                                                           
    class Gcd 
      : public Binary_function< Type, Type, Type > {
    public:
        Type operator()( const Type& x, const Type& y ) const {
            // By definition gcd(0,0) == 0
          if( x == Type(0) && y == Type(0) )
            return Type(0);
            
          return CGAL::Nef::gcd( x, y );
        }
        CGAL_IMPLICIT_INTEROPERABLE_BINARY_OPERATOR( Type )
    };
};

template <class NT> class Real_embeddable_traits< Nef_polynomial<NT> > 
  : public Real_embeddable_traits_base< Nef_polynomial<NT> > {
  public:
    typedef Nef_polynomial<NT> Type;
    class Abs 
        : public Unary_function< Type, Type> {
    public:
        Type inline operator()( const Type& x ) const {
            return (CGAL::Nef::sign( x ) == CGAL::NEGATIVE)? -x : x;
        }        
    };

    class Sign 
      : public Unary_function< Type, CGAL::Sign > {
      public:
        CGAL::Sign inline operator()( const Type& x ) const {
            return CGAL::Nef::sign( x );
        }        
    };
    
    class Compare 
      : public Binary_function< Type, Type,
                                CGAL::Comparison_result > {
      public:
        CGAL::Comparison_result inline operator()( 
                const Type& x, 
                const Type& y ) const {
            return (CGAL::Comparison_result) CGAL::Nef::sign( x - y );
        }
    };
    
    class To_double 
      : public Unary_function< Type, double > {
      public:
        double inline operator()( const Type& p ) const {
            return CGAL::to_double(
                    p.eval_at(Nef_polynomial<NT>::infi_maximal_value()));
        }
    };
    
    class To_interval 
      : public Unary_function< Type, std::pair< double, double > > {
      public:
        std::pair<double, double> operator()( const Type& p ) const {
            return CGAL::to_interval(p.eval_at(Nef_polynomial<NT>::infi_maximal_value()));
        }
    };
};

CGAL_END_NAMESPACE

#endif  // CGAL_NEF_POLYNOMIAL_H